1. Field
The present disclosure relates generally to wireless communications, and more specifically to various techniques for preamble capture and medium access control.
2. Background
Carrier Sense Multiple Access (CSMA) are widely used in wireless communication systems for medium access control. With CSMA, a wireless device senses the medium through energy detection and transmit only when the medium is free.
A common problem in wireless communications occurs when two or more wireless devices attempt to transmit data to the same receiving wireless device. In this case, one of the transmitting wireless devices tends to dominate the channel and transmits data continuously, while the other transmitting wireless device experiences a long delay and poor fairness. In CSMA systems, fairness is achieved by inserting radio silence intervals between consecutive transmissions so that other wireless devices can sense a free medium and begin their transmissions.
Carrier sense is difficult to implement in Impulse-Radio Ultra-Wideband (IR-UWB) systems because the transmission power is usually below noise level. Without carrier sense, the radio silence interval needs to be large with respect to the length of the frame transmissions. This tends to reduce the throughput of the system.
Accordingly, there is a need in the art for improved methods for facilitating medium access control and to achieve a high level of fairness among transmitting wireless devices in IR-UWB systems. These methods should be extendable to other wireless communication systems.